1Department of General Surgery, 2Department of Emergency
Medicine (Division of Surgery), 3Department of Underwater
Medicine, 4Department of Physiology, 5Department of Toxicology,
6Department of Pathology, Gülhane Military Medical Academy,
Gülhane School of Medicine Ankara, Turkey

Received December 13, 2002
Accepted June 12, 2003

Summary
It has been demonstrated that hyperbaric oxygen (HBO) is useful
as an adjunctive therapy for Crohn's disease. However, its
effects on ulcerative colitis have not been investigated. In the
present study, HBO was tested for acetic acid-induced colitis,
and antioxidant systems were evaluated to clarify its possible
mode of action. Thirty-six Sprague-Dawley rats were randomly
divided into three groups: sham control (Group I), colitis
induced by acetic acid without any therapy (Group II), colitis
induced by acetic acid and treated with HBO (Group III). HBO was
given for 5 days, 2 sessions per day at 2.5-fold absolute
atmosphere pressure (ATA) for a period of 90 min in rats in
which colitis had been induced (Group III). Rats were sacrificed
on the 5th day after the procedure. Superoxide dismutase (SOD),
malondialdehyde (MDA) and glutathione peroxidase (GSH Px)
activity were measured in the intestinal tissue and erythrocyte
lysate. MDA and GSH Px were also determined in the plasma.
Whereas MDA levels in erythrocyte, plasma and intestinal tissue
were decreased, the levels of GSH Px and SOD were significantly
increased in Group III as compared to those of Group II. The
results of our study suggest that hyperbaric oxygen therapy has
beneficial effects on the course of experimental distal colitis
and that antioxidant systems may be involved in its mode of
action.